ABT. 21. PARASITES OF SHARKS AND SKATES — LINTON. 87 



Carcharhinus comDiersonii. 



1923, August 25 : About 50 cysts collected from the submucosa of 

 the stomach of a 202-centimeter shark, associated with large numbers 

 of cysts of O. crenacolle^ all rather small, 10 by 5 mm. 



1923, August 29: 150 cysts from submucosa of stomach of a 230- 

 centimeter shark, associated with very numerous cysts of O. crena- 

 colle. 



G archarhinus limbatus. 



1915, August 6: Several, associated with Otobothnum crenacoUe^ 

 encysted in submucosa of stomach; one cyst measured 8 by 3.5 mm. 

 in the two principal diameters. 



1918, July 13: Many cysts in submucosa of stomach; 8 by 3 mm., 

 and smaller; one plerocercus when liberated from its cyst assumed 

 the shape characteristic of the species, in which the end in which the 

 scolex is lodged, became globular, 2 mm. in diameter, while the re- 

 mainder of the plerocercus was very variable, sometimes forming a 

 linear extension as much as 28 mm. in length. 



O archarhinus milh erti. 



1922, July 3 : 1 cyst on serous coat of stomach : scolex, when placed 

 in fresli water everted the proboscides. 



(U.S.N.M., Helm. Coll. 7719.) 



Garch arhinvs ohscurus. 



1905, August 11 : 2, between submucous and muscular coats of 

 stomach ; characteristic cysts and plerocerci. 



1911, August 3: 4, encysted in submucosa at posterior end of 

 cardiac portion of stomach; dimensions of largest plerocercus, 

 diameter of globular portion, 3 mm., length of remaining portion, 

 when fully extended, 38, diameter, 0.5. 



1912, September 12: Several transparent, oval-elliptical cysts in 

 serous coat of stomach, and on spleen; one cyst measured 6 by 4.5 

 mm; plerocerci of usual character, scolex contained in dense, ivory- 

 white, globular portion, remaining portion variable, usually more or 

 less linear. 



GynosGion regalis. 



1905, July 14: 1 elongated cyst, on mesentery, 5 fish examined. 

 July 15. 1 ; length of plerocercus 94 mm. ; globular portion active, 

 lengthening to 5 or 6 mm., and contracting to sphere, 2.5 mm. in 

 diameter. 



Gdleocerdo arcficus. 



1907, August 7:1, encysted in stomach wall near esophagus. 



Pai 'd lick t hys de n tat us. 



1904, August 8 : 2 plerocerci, no scoleces. 



